3. e1d3  3... e8f6  4. h1g3  4... h8g6 Only four moves have been played and White's position is already difficult, something that can only happen at this level in a freestyle game. Carlsen has problems finishing his development: If e2-e4 is played, then he loses castling rights after the pawn exchange and a check on g4 (although he will allow this later). I thought of 5.Qf2 to castle on the kingside, but then the plan of a6 or a5 followed by Ba7 is unpleasant. Another plan is to develop the bishop to a2 (Carlsen's attempt) or c2 (with 5.c3). 5. a2a4 